A pilots' strike on Virgin Atlantic would leave "an indelible scar on the company", the airline's boss Sir Richard Branson said today.

The pilots' union Balpa has said that it will announce strike dates from tomorrow unless a dispute over pay is resolved.

Today, Sir Richard wrote to his airline's pilots saying he was "extremely sad" about the threat of strike action and urged Balpa to arrange talks with Virgin management.

Sir Richard also said he would be prepared to have a private meeting with pilots to answer questions about the future.

Balpa has voted overwhelmingly for strike action in protest at a 4% pay rise following a number of pay freezes. The union's general secretary Jim McAuslan last week urged Sir Richard to become personally involved.

In his letter today, Sir Richard said: "I have looked at the details of your offer and believe it is fair. From the company's point of view possibly a little too fair.

"It is one of the best in the industry, along with many other commitments that offer real value to you."

He went on: "Unless Balpa withdraws its threat very soon, it will leave an indelible scar on the company, impact customers' trust in us and damage the unique and friendly culture at Virgin Atlantic.

"It will affect jobs and it will make it very difficult for the company to afford the current offer on the table."

Sir Richard added: "I was obviously extremely sad to see threats of strike action in the press as these negative comments will have already damaged the reputation of our airline and the trust our customers place in us - which we rely on so heavily. They have also played into the hands of our larger rivals."

He continued: "Your union asked me to get involved and I've looked at all the facts and believe that our management have made the best offer it can.

"Our chief operating officer, Steve Griffiths, is ready to meet with Balpa and your committee again and I appeal to you to insist that they do so as soon as possible.

"Your union representative also publicly asked to meet with me personally. I believe that would only cause more publicity which would further damage the airline and I am not best placed to deal with the details of the negotiation.

"However, I would be happy to have a private meeting with as many pilots that are available to answer your questions about the future of the airline. I will have a member of my team get in touch regarding potential times."